This study is a randomized clinical trial that assesses the impact of 2 types of enhanced physical activity programs in elderly persons with a systolic blood pressure of 130-159 mmHg. Sixty-two participants were randomly assigned to either (a) an aerobic training program or (b) Tai Chi. Active intervention lasted 3 months; the maintenance phase will last 9 months. Follow-up will end in 5/97. The primary outcome variable is blood pressure; secondary outcome variables include serum lipids. Data from this trial will be used in the design of a large scale clinical trial that will determine whether physical activity can control blood pressure without the need for medication.